Fill in the Blanks Linear graphOnline version The activity is focus on basic concepts of linear function by Paula Bernat andreu 1 points parallel linear powers negative plot mx perpendicular check positive A function is any function that graphs to a straight line . What this means mathematically is that a linear function has either one or two variables with no exponents or . The equation of a straigh line is usually written this way y = + b . A line with a slope rises from left to right whereas a line with a slope falls from left to right . If two lines have the same slope the lines are said to be . However , if they have negative reciprocal slope the lines are called . You can the graph of a linear function using just two . If you are unsure you can use more points to double - .